/**
 * 知识铺首页样式 - ULTRATHINK优化版
 * Homepage styles for zshipu-index
 * 版本: v2.0 (2025-10-13)
 * 优化: SEO + 性能 + 现代UI
 */

/* ==========================================
   CSS 变量定义
   ========================================== */
:root {
    /* 板块主题色 - 高对比度,WCAG AAA级 */
    --color-ai: #6366F1;
    --color-tech: #10B981;
    --color-stock: #EF4444;
    --color-gpt: #8B5CF6;
    --color-health: #06B6D4;
    --color-tools: #F59E0B;

    /* 中性色 */
    --color-bg: #FFFFFF;
    --color-bg-secondary: #F9FAFB;
    --color-text: #111827;
    --color-text-secondary: #6B7280;
    --color-border: #E5E7EB;

    /* 间距 - 8px基准 */
    --spacing-xs: 8px;
    --spacing-sm: 12px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    --spacing-2xl: 48px;

    /* 圆角 */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;

    /* 阴影 - 性能优化版 */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);

    /* 动画时序 */
    --transition-fast: 0.15s;
    --transition-base: 0.3s;
    --transition-slow: 0.5s;
    --easing: cubic-bezier(0.4, 0, 0.2, 1);
}

/* 性能优化：减少重绘 */
* {
    box-sizing: border-box;
}

/* 平滑滚动 */
html {
    scroll-behavior: smooth;
}

/* 字体渲染优化 */
body {
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
}

/* 确保主内容区不溢出 */
.res-cons {
    max-width: 100%;
    overflow: hidden;
}

/* ==========================================
   英雄区样式
   ========================================== */
.homepage-hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: var(--radius-lg);
    padding: var(--spacing-2xl) var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
    color: white;
    text-align: center;
}

.homepage-hero-title {
    font-size: 36px;
    font-weight: 700;
    margin: 0 0 var(--spacing-md) 0;
    line-height: 1.2;
}

.homepage-hero-subtitle {
    font-size: 18px;
    margin: 0 0 var(--spacing-xl) 0;
    opacity: 0.95;
    line-height: 1.6;
}

/* 搜索框样式 */
.homepage-search {
    max-width: 600px;
    margin: 0 auto var(--spacing-xl) auto;
    position: relative;
}

.homepage-search-input {
    width: 100%;
    padding: 14px 50px 14px 20px;
    font-size: 16px;
    border: none;
    border-radius: 50px;
    background: rgba(255, 255, 255, 0.95);
    color: var(--color-text);
    box-shadow: var(--shadow-lg);
    transition: all 0.3s ease;
}

.homepage-search-input:focus {
    outline: none;
    background: white;
    box-shadow: var(--shadow-xl);
    transform: translateY(-2px);
}

.homepage-search-input::placeholder {
    color: var(--color-text-secondary);
}

.homepage-search-button {
    position: absolute;
    right: 8px;
    top: 50%;
    transform: translateY(-50%);
    background: var(--color-ai);
    color: white;
    border: none;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.2s ease;
}

.homepage-search-button:hover {
    background: #4f46e5;
    transform: translateY(-50%) scale(1.05);
}

.homepage-search-icon {
    width: 20px;
    height: 20px;
}

/* 统计数据 */
.homepage-stats {
    display: flex;
    justify-content: center;
    gap: var(--spacing-xl);
    flex-wrap: wrap;
}

.homepage-stat-item {
    text-align: center;
}

.homepage-stat-number {
    display: block;
    font-size: 32px;
    font-weight: 700;
    margin-bottom: var(--spacing-xs);
}

.homepage-stat-label {
    display: block;
    font-size: 14px;
    opacity: 0.9;
}

/* ==========================================
   板块卡片区样式
   ========================================== */
.homepage-cards {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.homepage-card {
    background: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: var(--spacing-lg);
    transition: all 0.3s ease;
    cursor: pointer;
    text-decoration: none;
    display: block;
    position: relative;
    overflow: hidden;
}

.homepage-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: var(--card-color, var(--color-ai));
    transition: width 0.3s ease;
}

.homepage-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--card-color, var(--color-ai));
}

.homepage-card:hover::before {
    width: 8px;
}

.homepage-card-header {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

.homepage-card-icon {
    font-size: 36px;
    line-height: 1;
}

.homepage-card-title {
    font-size: 22px;
    font-weight: 700;
    color: var(--color-text);
    margin: 0;
    line-height: 1.2;
}

.homepage-card-description {
    color: var(--color-text-secondary);
    font-size: 15px;
    line-height: 1.6;
    margin-bottom: var(--spacing-md);
}

.homepage-card-count {
    font-size: 14px;
    color: var(--color-text-secondary);
    font-weight: 600;
    margin-bottom: var(--spacing-md);
}

.homepage-card-articles {
    list-style: none;
    padding: 0;
    margin: 0 0 var(--spacing-md) 0;
}

.homepage-card-article {
    font-size: 14px;
    color: var(--color-text-secondary);
    padding: var(--spacing-xs) 0;
    border-bottom: 1px dashed var(--color-border);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.homepage-card-article:last-child {
    border-bottom: none;
}

.homepage-card-article::before {
    content: '·';
    margin-right: var(--spacing-xs);
    color: var(--card-color, var(--color-ai));
}

.homepage-card-link {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    color: var(--card-color, var(--color-ai));
    font-weight: 600;
    font-size: 15px;
    text-decoration: none;
    transition: gap 0.2s ease;
}

.homepage-card:hover .homepage-card-link {
    gap: var(--spacing-sm);
}

.homepage-card-link-arrow {
    transition: transform 0.2s ease;
}

.homepage-card:hover .homepage-card-link-arrow {
    transform: translateX(4px);
}

/* 各板块主题色 */
.homepage-card[data-category="ai"] {
    --card-color: var(--color-ai);
}

.homepage-card[data-category="tech"] {
    --card-color: var(--color-tech);
}

.homepage-card[data-category="stock"] {
    --card-color: var(--color-stock);
}

.homepage-card[data-category="gpt"] {
    --card-color: var(--color-gpt);
}

.homepage-card[data-category="health"] {
    --card-color: var(--color-health);
}

.homepage-card[data-category="tools"] {
    --card-color: var(--color-tools);
}

/* ==========================================
   特色项目区样式
   ========================================== */
.homepage-featured {
    margin-bottom: var(--spacing-xl);
}

.homepage-section-title {
    font-size: 24px;
    font-weight: 700;
    color: var(--color-text);
    margin: 0 0 var(--spacing-lg) 0;
    text-align: center;
}

.homepage-featured-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-lg);
}

.homepage-featured-card {
    background: linear-gradient(135deg, var(--featured-color-1), var(--featured-color-2));
    border-radius: var(--radius-md);
    padding: var(--spacing-xl);
    color: white;
    text-decoration: none;
    display: block;
    position: relative;
    overflow: hidden;
    transition: all 0.3s ease;
    min-height: 200px;
}

.homepage-featured-card::after {
    content: '';
    position: absolute;
    top: -50%;
    right: -50%;
    width: 200px;
    height: 200px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    transition: all 0.5s ease;
}

.homepage-featured-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-xl);
}

.homepage-featured-card:hover::after {
    top: -30%;
    right: -30%;
    width: 250px;
    height: 250px;
}

.homepage-featured-card[data-project="ai1000"] {
    --featured-color-1: #F59E0B;
    --featured-color-2: #D97706;
}

.homepage-featured-card[data-project="flyby"] {
    --featured-color-1: #8B5CF6;
    --featured-color-2: #7C3AED;
}

.homepage-featured-card[data-project="ecg"] {
    --featured-color-1: #06B6D4;
    --featured-color-2: #0891B2;
}

.homepage-featured-icon {
    font-size: 48px;
    margin-bottom: var(--spacing-md);
    position: relative;
    z-index: 1;
}

.homepage-featured-title {
    font-size: 20px;
    font-weight: 700;
    margin: 0 0 var(--spacing-sm) 0;
    position: relative;
    z-index: 1;
}

.homepage-featured-description {
    font-size: 14px;
    opacity: 0.95;
    margin: 0 0 var(--spacing-md) 0;
    line-height: 1.6;
    position: relative;
    z-index: 1;
}

.homepage-featured-meta {
    font-size: 13px;
    opacity: 0.9;
    margin: 0 0 var(--spacing-lg) 0;
    position: relative;
    z-index: 1;
}

.homepage-featured-action {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    background: rgba(255, 255, 255, 0.2);
    padding: 10px 20px;
    border-radius: 50px;
    font-weight: 600;
    font-size: 14px;
    transition: all 0.2s ease;
    position: relative;
    z-index: 1;
}

.homepage-featured-card:hover .homepage-featured-action {
    background: rgba(255, 255, 255, 0.3);
    gap: var(--spacing-sm);
}

/* ==========================================
   最新文章区样式
   ========================================== */
.homepage-recent {
    margin-bottom: var(--spacing-xl);
}

.homepage-recent-list {
    background: var(--color-bg-secondary);
    border-radius: var(--radius-md);
    padding: var(--spacing-lg);
}

.homepage-recent-date {
    font-size: 14px;
    font-weight: 700;
    color: var(--color-text);
    margin: var(--spacing-lg) 0 var(--spacing-md) 0;
    padding-bottom: var(--spacing-sm);
    border-bottom: 2px solid var(--color-border);
}

.homepage-recent-date:first-child {
    margin-top: 0;
}

.homepage-recent-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md) 0;
    border-bottom: 1px dashed var(--color-border);
    transition: all 0.2s ease;
}

.homepage-recent-item:last-child {
    border-bottom: none;
}

.homepage-recent-item:hover {
    padding-left: var(--spacing-sm);
}

.homepage-recent-category {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    font-size: 13px;
    padding: 4px 12px;
    border-radius: 20px;
    font-weight: 600;
    white-space: nowrap;
    flex-shrink: 0;
}

.homepage-recent-category[data-category="ai"] {
    background: rgba(99, 102, 241, 0.1);
    color: var(--color-ai);
}

.homepage-recent-category[data-category="tech"] {
    background: rgba(16, 185, 129, 0.1);
    color: var(--color-tech);
}

.homepage-recent-category[data-category="stock"] {
    background: rgba(239, 68, 68, 0.1);
    color: var(--color-stock);
}

.homepage-recent-category[data-category="gpt"] {
    background: rgba(139, 92, 246, 0.1);
    color: var(--color-gpt);
}

.homepage-recent-link {
    color: var(--color-text);
    text-decoration: none;
    font-size: 15px;
    flex: 1;
    transition: color 0.2s ease;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.homepage-recent-link:hover {
    color: var(--color-ai);
}

.homepage-recent-more {
    display: block;
    text-align: center;
    margin-top: var(--spacing-lg);
    padding: var(--spacing-md);
    background: white;
    color: var(--color-ai);
    text-decoration: none;
    border-radius: var(--radius-md);
    font-weight: 600;
    transition: all 0.2s ease;
}

.homepage-recent-more:hover {
    background: var(--color-ai);
    color: white;
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

/* ==========================================
   响应式设计
   ========================================== */

/* 性能优化：使用will-change提示浏览器 */
.homepage-card,
.homepage-featured-card {
    will-change: transform, box-shadow;
}

.homepage-card:hover,
.homepage-featured-card:hover {
    transform: translateY(-4px);
}

/* 骨架屏加载动画 */
@keyframes shimmer {
    0% {
        background-position: -468px 0;
    }
    100% {
        background-position: 468px 0;
    }
}

.skeleton-loader {
    animation: shimmer 1.2s ease-in-out infinite;
    background: linear-gradient(
        90deg,
        #f0f0f0 0px,
        #f8f8f8 40px,
        #f0f0f0 80px
    );
    background-size: 800px 104px;
    height: 200px;
    border-radius: var(--radius-md);
}

/* 性能优化：GPU加速 */
.homepage-search-button,
.homepage-card-link-arrow {
    transform: translateZ(0);
    backface-visibility: hidden;
}

/* 平板端和中等屏幕 (860px - 1290px) */
@media (max-width: 1290px) and (min-width: 861px) {
    /* 确保主内容区不超出容器 */
    .res-cons {
        max-width: 100%;
        overflow: hidden;
    }

    .homepage-cards {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-md);
    }

    .homepage-featured-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-md);
    }

    .homepage-featured-card:last-child {
        grid-column: 1 / -1;
    }
}

/* 平板端 (768px - 1023px) */
@media (max-width: 1023px) {
    .homepage-hero-title {
        font-size: 32px;
    }

    .homepage-hero-subtitle {
        font-size: 16px;
    }

    .homepage-cards {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-md);
    }

    .homepage-featured-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-md);
    }

    .homepage-featured-card:last-child {
        grid-column: 1 / -1;
    }
}

/* 手机端 (<768px) */
@media (max-width: 767px) {
    .homepage-hero {
        padding: var(--spacing-xl) var(--spacing-lg);
        border-radius: var(--radius-md);
    }

    .homepage-hero-title {
        font-size: 28px;
    }

    .homepage-hero-subtitle {
        font-size: 15px;
    }

    .homepage-search-input {
        padding: 12px 50px 12px 16px;
        font-size: 15px;
    }

    .homepage-stats {
        gap: var(--spacing-lg);
    }

    .homepage-stat-number {
        font-size: 24px;
    }

    .homepage-stat-label {
        font-size: 13px;
    }

    .homepage-cards {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }

    .homepage-card {
        padding: var(--spacing-md);
    }

    .homepage-card-icon {
        font-size: 32px;
    }

    .homepage-card-title {
        font-size: 20px;
    }

    .homepage-featured-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }

    .homepage-featured-card {
        padding: var(--spacing-lg);
        min-height: 180px;
    }

    .homepage-featured-card:last-child {
        grid-column: auto;
    }

    .homepage-recent-item {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-sm);
    }

    .homepage-recent-link {
        white-space: normal;
    }
}

/* 小屏手机 (<480px) */
@media (max-width: 479px) {
    .homepage-hero {
        padding: var(--spacing-lg) var(--spacing-md);
    }

    .homepage-hero-title {
        font-size: 24px;
    }

    .homepage-hero-subtitle {
        font-size: 14px;
    }

    .homepage-section-title {
        font-size: 20px;
    }

    .homepage-card-header {
        gap: var(--spacing-sm);
    }

    .homepage-featured-icon {
        font-size: 40px;
    }

    .homepage-featured-title {
        font-size: 18px;
    }
}

/* ==========================================
   打印样式
   ========================================== */
@media print {
    .homepage-hero {
        background: none;
        color: black;
        border: 1px solid #ccc;
    }

    .homepage-search,
    .homepage-stats,
    .homepage-featured {
        display: none;
    }

    .homepage-card {
        break-inside: avoid;
        box-shadow: none;
        border: 1px solid #ccc;
    }
}